Middle ear problems in childhood.

No single factor is as yet known which could be used to predict the possible development of rAOM in infants and children. However, some circumstantial evidence can be seen. Thus, an AOM début before the age of six months in a child with a family history of recurrent otitis indicates a clear risk of multiple recurrent episodes. Other 'intrinsic factors' speaking in favour of rAOM are low concentrations of specific IgG antibodies against pneumococcus type 6A in cord serum and a presence of the hereditary HLA-antigen A2 on the surfaces of white blood cells. Extrinsic factors' such as type of day-care, passive exposure to smoking at home and poor housing seem to increase the risk but do probably not constitute the definite cause of rAOM.